


misery loves company

by Profundus



Category: Haikyuu!!
Genre: Alpha/Beta/Omega Dynamics, Alpha/Omega, Ambiguous Relationships, M/M, Mating Cycles/In Heat, Omega Verse, Semi-explicit sex, Sibling Incest
Language: English
Status: Completed
Published: 2020-12-02
Updated: 2020-12-02
Packaged: 2021-03-10 06:21:16
Rating: Mature
Warnings: Underage
Chapters: 1
Words: 2,354
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27845938
Author URL: https://archiveofourown.org/users/Profundus/pseuds/Profundus
Summary: Rooms, beds, meals, pranks, punishments, passions, opinions – the Miya twins share everything.When Osamu asks Atsumu to share something else, too, he doesn't know what to make of the result.
Relationships: Miya Atsumu/Miya Osamu
Comments: 3
Kudos: 181





	misery loves company

**Author's Note:**

  * For [tisapear](https://archiveofourown.org/users/tisapear/gifts).



"Tsuuuumu," Osamu drawls as he tosses the ball up to the ceiling, to the comforting whiteness of oblivion, the same oblivion that is Atsumu on the other side of the room.

His twin doesn't respond immediately. He just keeps staring at his phone and the muffled song blaring from the one earphone he isn't currently using to torture his eardrums brings out an annoyance in Osamu that barely deserves to be called that. It's not Atsumu's choice of musical entertainment that's bothering him, it's the ever-approaching date on the dog-eared and worn pocket calendar he sees peeking from his schoolbag even now.

"Tsumu," he repeats, this time with pressing urgency.

He wants to just get this over with, wants to have it out of the way so he can focus on something else. Somewhere in the twisted corner of his mind, he knows he won't be able to anyway, no matter what kind of answer he'll get from Atsumu.

Either way, he'll be at war with himself in less than a few days for having asked the stupid question in the first place. An afterthought, an idea starts to glow within the sinister scowl on his face.

So he won't ask.

He'll demand.

Osamu tosses the ball. Not at the oblivious ceiling, but at the oblivious guy across the room, sprawled out on his bed like he's working on a starfish-impersonation.

"What d'ya want, dimwit?" Atsumu groans and rolls over to look at his brother, all pouts and furrowed brows, but it turns to subtle concern like he's not sure whether to be surprised that it's been the ball and not Osamu's fist that has hit his face mere seconds ago.

That's usually how they react upon being ignored by the other. Punches and kicks have a way stronger _stop pretending you can't hear me-_ effect than repeating a name over and over like a broken record.

Osamu clenches his sheets. His mind is racing, his thoughts stumbling over each other, but enough, _enough._ This is Atsumu and Osamu has enough dirt on him to know his twin will keep that big, stupid mouth of his shut, even if this goes south. The words still stick to his tongue, holding on, not wanting to be spoken. He spits them out.

"Share my heat."

He's got a list of emotions to expect. On top of said list: disgust. Next would be disbelief. Relaxed amusement because something ridiculous as that can only be hoax takes third place.

The sarcastic raise of an eyebrow, the corner of plush lips turned up into a lopsided grin is within the expected range, then. Osamu squints. His heart hasn't stopped killing him with powerful pounds into the vacancy of his ribcage yet. There's still the response to wait for because even a statement requires an answer.

"Where'd that come from?" Atsumu asks slowly, like he needs Osamu to listen well to him. "Did ya perhaps get a blow to your pretty head? What prompted that bullshit? No, of course I won't."

Pretty he says, like it isn't a compliment to himself, and the clock ticks to remind Osamu every second is a wasted second and brings him closer to the red scribble on his calendar. His skin itches. He wants to crawl out of it.

"I'm not takin' a No."

The surprise overthrows both of them. Osamu hasn't meant to say that and now the air is knocked from his lungs. At least he can't say anything even more stupid when he's busy breathing.

Atsumu gets up. Every little motion of his body is intentional. Control comes so naturally to him like the tosses in volleyball, dominance flocks to him like his spikers do – a slow and weighty sense of supremacy that makes its home on the court and every room Atsumu enters. He doesn't have to shine with words when his presence does a formidable job at emanating that this is an Alpha who doesn't take bullshit from anyone.

"Why would ya say something like that in the first place?" It's not often that Atsumu lacks a smirk, a grin, a smile when he's talking. It's a palpable absence. "Ain't got enough Alphas chasing yer tail yet? I can help with that. Some guys got an eye on ya, Samu. Some even two. And some would like their hands on ya, not their eyes."

It's hard to look away and it's hard to look at him.

"I said, share my heat."

"Well, I said no. Find someone else to push that on, wontcha."

Osamu feels like he's being held underwater, rippling surface in sight, grazing his fingertips like a messy set-up – the sensation is there, but he lacks the momentum to make anything of it.

"I don't trust anyone else!" he yells and jumps from his bed because only now does he realize Atsumu is looking down on him, has been for longer than he can remember and the familiar reek of terror that comes from himself is mirrored in Atsumu's eyes.

Sometimes, he's awake at night and thinks of all that's unsaid between them, and how unsettling it would be to start saying all those things now. It's not just unsettling, Osamu finds out, it's downright horrifying.

"Ain't it _you_ who keeps sayin' you don't trust me?"

Atsumu shoves both hands into his pockets as he hangs over him and breathes into Osamu's space, grins into his face, but there's a panicked edge to it. So it's not just horrifying to the one saying those things. For a moment, Osamu wonders what it would be like to hear it come from Atsumu's mouth. Maybe he would look like this too, maybe his façade would crack at the edges too. Maybe he wouldn't be able to catch up with his own mind either.

"I don't trust ya with things that benefit only one of us," he snarls, but his lungs are out of air and his head is out of thoughts.

"So what's my benefit from sharing yer heat?"

Osamu knows he doesn't mean to, but the silence shelved in their minds is threatening to burst into words they aren't ready for.

"Oh come on. I have to talk about the birds and the bees now?" he asks and tries to sound lighthearted but that's difficult when his heart is what's weighing him down. It does the job though, and Atsumu leaves the discomfort of their breaths mingling.

Not because he's backing down, but because space means a reprieve, a moment to overthink his next move. Stale. Truce. Time to sort out his options, his choices. Maybe it's good that he always saves up what little critical thinking skills he possesses. Osamu looks down at his hands, their hands, so similar, just like the rest of their bodies on the outside.

They've shared everything.

First breath _you refused to breathe without me do you remember do you_ first steps _we couldn't walk if we weren't holding each other_ first words _mama we said it at the same time we kept saying it back and forth at night in our bed_ first fight _so unfair so disgustingly unfair that you are an Alpha and I'm stuck as an Omega not fair not fair not fair not fair—_

"It's not yer first heat, right?"

He asks like he regrets. Osamu just doesn't know what.

"Eleventh."

Ten times suffering and ten times crying and ten times overheating on a fever and ten times tearing at his own skin for being so ill-fitting on the body of someone who should be an Alpha like his twin – ten times living through the same misery.

Atsumu sits back down on his bed. The earphones are dangling over the edge, swinging left to right, right to left. It looks like he's thinking, but Osamu knows he isn't. He's just being considerate. Quiet. The room smells like distressed Omega now. Memories are harder to withstand than reality.

"How many days do ya usually take off?"

"Eight."

"Gotcha," Atsumu says as if he's just confirming what to get from the konbini for lunch.

"Let me go through your closet," Osamu responds and wonders if they sell unbroken hearts.

It's not the first time he's nesting. The first time probably has been way back when Atsumu has gotten into his first fight in pre-school, concussion and bedrest and his brother's instinct to keep him warm and safe leaving him to wake up in a vast array of pillows and blankets and stuffed animals, neatly shaped into a small nest. Just big enough for two little bodies slotting together like pieces of a whole.

Now, he knows how to do it properly and it's a vicious flood of first-time satisfaction because his nest smells like Alpha now, blankets interwoven with shirts and sweatpants and the sheets from Atsumu's bed.

"Ehh, it looks so soft. How d'ya do it?"

He steps into it without permission and Osamu snarls for a moment before the pile of clothes dropped before his knees smooths over the prickle on his skin.

"None of yer fuckin' business. Get out until I'm done, I don't need you here."

Even so, Atsumu keeps standing there for a moment, but he brushes his hand against the doorframe on his way out like it's unintentional, nonchalant, when the scent he leaves behind is anything but.

The nest Osamu is building for them looks soft, just like his brother, but he knows to be wary of edges and sharp points. They hit where it hurts the most just when everyone has already forgotten about them. There isn't much more left in his closet and drawers that hasn't fallen prey to Osamu's nesting instinct yet, so Atsumu curls up on the bed that doesn't belong to him and waits.

He waits for two entire days until Osamu stops growling every time he approaches the nest, until the apprehensive glares turn to needy breaths of his name, until he's being refused to leave just like he's been refused to enter before.

"We need more water, ya damn idiot," he says on the third day and tries to stroke the fever back under Osamu's skin, pries the hands off of him that cling to his arm. "Let me just get some or we won't make it all week. I won't be long."

"No."

Atsumu groans and rolls them over. There's not much physical advantage he can be proud of, but at least there's no fire in his stomach rendering him helpless. One hand, two wrists. He holds him down with as much force as he dares and Osamu is pliant and quiet for once, maybe because the fever is leaving him without much perception of his surroundings, or because Atsumu is heavy on top of him.

There's a primal delight in the vulnerability of silver hair fanned out on the edge of their nest, in the sensation of Osamu's body arching to the fingertips padding down his side.

"Shh. So impatient," Atsumu mutters and forgets about the water, forgets about the place outside the narrow doorway, forgets about their last names, and just remembers Osamu has asked him to do this and he can enjoy what he has to offer in front of the gods and the entire world.

He smirks, not so much from the knowledge but from the way Osamu claws at his back and bucks his hips and moans into Atsumu's mouth that finally finds his own and it's difficult to say if he's just so desperate or if Atsumu is just being rough when he bunches up the loose shirt and kisses his way down along quivering muscles and straining sinew.

_There's a first time for everything, no?_

It's not a thought, just an extension of his reverence when he feels Osamu hot and tight around him and reads from the high keen that an eleventh heat doesn't mean an eleventh time of being relieved from it. It's violent and short, but Atsumu likes the abruptness, likes that his touch is the first one on Osamu's body and the only one that draws out such noises from him, likes that Osamu can't decide whether to grind down on him or push up into his kisses.

He feels himself getting on the same miserable high, feels the arousal sweeping over him and bleeding impatience into his system, but he draws it out just to hear Osamu scream. Not his name, but that's alright, Atsumu thinks, that's okay. There's plenty of time for it later.

He changes his angle and the depth and pulls Osamu into his lap, guides his hips to the point where he fears he might break bones if he tightens his grip even further and yet can't help it because it's too much for Osamu but he needs him out of that first wave and so he just leans up and whispers, whispers _good boy, good boy, bein' so damn good for nii-chan, aren't ya_ and Osamu falls forward with a cry at the last thrust.

It's enough, enough to leave him in an absent white place, and the oblivion in Atsumu's eyes when he opens his own is enough to push him straight into the second wave. It's a vicious brutality, to face Atsumu like this, but he endures it. For an entire week, he endures the unknowing glances and grins and mutters against his skin and the relief of Atsumu waking him _oi, you're back in heat, come here, come here before it gets painful_ in the dead of night and the bright of day and he curls his fingers into Atsumu's hair and drinks up the resounding sigh to revel in it as long as it lasts.

"Samu," Atsumu says, on the edge of the nest after the eighth day, and Osamu looks up from where he's been sleeping, curled up in a shirt _fits perfectly doesn't it_ that isn't his own.

"Tsumu," he echoes.

Atsumu doesn't look back at him as he stands up, hands on his knees for just a moment and Osamu follows the ripple of his shoulder blades.

"Share my rut."

**Author's Note:**

> My wife roped me into the Miya-addiction. Nobody knows how much I love her.


End file.
